With ever increasing operational speeds of electronic devices in electronic systems, such as computer systems, relatively large amounts of electromagnetic (EM) emissions are generated by the electronic devices during operation. Such EM emissions cause electromagnetic interference (EMI) that may interfere with operations of other electronic systems. Consequently, government agencies have established regulations to reduce EM emissions from electronic systems.
A technique that is widely used to reduce EMI is the use of EMI shields. Often, an EMI shield is in the form of a shielded enclosure provided by the outside cabinet or housing of an electronic system. In other cases, EMI shields in the form of metal cages have been provided within system enclosures to cover individual electronic devices for EMI suppression during operation of such individual electronic devices.
An electronic system typically includes one or more circuit boards on which electronic devices are mounted. The use of metal cages for individual electronic devices often takes up valuable real estate on the surface of a circuit board on which electronic devices are mounted. Decreased availability of the surface area of the circuit board for mounting electronic devices may mean that larger circuit boards have to be used to mount the same number of electronic devices, which may lead to increased manufacturing costs.
Another form of EMI shielding that has been employed includes EMI coating applied onto electronic devices on a surface of a circuit board. The EMI coating conforms to the shape of the electronic devices. However, an issue associated with the EMI coating is the difficulty associated with removing the coating in case access is desired of electronic devices for performing maintenance or upgrades. To remove any part of the EMI coating, a part of the EMI coating has to be cut away, which means that the EMI coating would be damaged.